JPS60222748A - Method and apparatus for measuring specific gravity - Google Patents

Abstract

PURPOSE:To simply and rapidly operate and calculate the specific gravity of body fluids, by propagating an ultrasonic wave through body fluids and operating a propagation speed and the temp. of body fluids. CONSTITUTION:A sensor part 2 is immersed in body fluids, for example, urine, blood, plasma or serum. The sensor part 2 consists of an ultrasonic wave transmitter-receiver 4, a reflective plate 3 and a temp. sensor 5 and the interval L0 between the reflective plate and the transmitter-receiver is fixed to be set to a setting device 6. An ultrasonic wave circuit is constituted of a sing-around circuit 8 and the information of a propagation speed V passes through a gate circuit 11 to enter CPU12. The change in the voltge of the temp. sensor 5 is converted to temp. information by a tamp. measuring circuit 9 while the temp. information enters CPU12 through an AD converter circuit 10 and the gate circuit 11. The relation of specific gravity, the temp. and the propagation speed is stored in a memory circuit 13 and specific gravity is operated by CPU12 and displayed by a display circuit 15 through the gate circuit 11 and an amplifier circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a specific gravity measuring method and apparatus for calculating the total specific gravity of a body fluid based on the ultrasonic propagation velocity in the body fluid and the temperature of the body fluid.

[Prior art]

Conventionally, the gravimetric method and floating scale method have been used to measure the total specific gravity of body fluids, but these methods require the preparation of large volumes of body fluids, such as urine, blood, blood, serum, etc. It is inconvenient for continuous and periodic measurements. Furthermore, the refraction method is also used as a method for measuring urine specific gravity, etc., but it has the drawback that it cannot measure the specific gravity of turbid beds and blood.

As a customization of ultrasound, it is known that its propagation speed depends on the composition and temperature of the bath liquid. When measuring the total specific gravity of a body fluid, the temperature of the body fluid is not necessarily constant, and conventional devices that measure the total specific gravity by changing the ultrasonic propagation velocity in the solution (for example, Japanese Patent Application Laid-open No. 108084/1984) This method has the disadvantage that accurate measurement is difficult because it is affected by temperature and cannot perform all calculations on the relationship between temperature and ultrasonic propagation velocity in the solution during measurement. In addition, there is a method for measuring specific gravity by comparing the propagation speed of a standard solution and a solution to be measured using ultrasonic waves (Japanese Patent Application Laid-Open No. 54-60968). However, it is difficult to accurately measure a wide range of specific gravity by comparing the propagation velocity with a standard solution for mixed liquids containing various components such as body fluids.

[Purpose of the invention]

In view of these drawbacks, the present invention is based on the principle that the ultrasonic propagation velocity depends on the components and temperature of the solution, and the present invention directly measures the ultrasonic propagation velocity in body fluids and the temperature of the body fluid, and measures the viscous body of the fluid. The object of the present invention is to provide a specific gravity measuring method for measuring the specific gravity of a body fluid by calculating the specific gravity of the body fluid, and an apparatus for easily and quickly calculating and calculating the specific gravity of a body fluid.

[Structure of the invention]

That is, the present invention provides a method for measuring specific gravity in which the specific gravity of a body fluid is calculated by propagating an ultrasonic wave into a body fluid and calculating from the ultrasound propagation velocity and the temperature of the body fluid; The entire ultrasonic wave is transmitted and received by a supported ultrasonic transducer and a reflecting plate that is supported while maintaining a constant propagation distance, and the entire ultrasonic propagation velocity is calculated from the ultrasonic propagation time and propagation distance in the body fluid,
It has a circuit that measures the total temperature within the body fluid with a temperature sensor and calculates the ultrasonic propagation velocity, body fluid temperature, and specific gravity of the body fluid.
This is a specific gravity measuring device that uses ultrasonic waves to measure the percentage of food consumed.

Hereinafter, the present invention will be described in detail with reference to the drawings and the like.

FIG. 1 is a block diagram illustrating an embodiment of a device according to the invention. In body fluids, such as urine, blood, plasma, serum, etc.
Ultrasonic transducer (4), reflector (8) and temperature sensor (
The sensor part (2) incorporating 5) is immersed. Distance between the reflector (8) and the ultrasonic transducer t4J.

is fixed by the sensor part (2), and the interval L
2LO, which is twice o, is the ultrasonic propagation distance. L.

is set in advance in the LO setting device (6).

The ultrasonic circuit consists of a sing-around circuit (8), and as shown in FIG. 8(a), the ultrasonic pulse wave (
20) is transmitted from the ultrasonic transducer (4) to the body fluid (1 circle), reflected by the reflecting plate (8), and transmitted again to the ultrasonic transducer (4).
), the ultrasonic pulse wave (21) shown in FIG. 8(b) is received. The time τ until the next ultrasonic pulse wave is transmitted
0 (2B), the ultrasonic pulse wave (22) in Fig. 8(al) is transmitted again from the ultrasonic transducer (4) after τo (2B) seconds have passed after reception. Fig. 8(c) ), the transmission k is repeated n+1 times (24) for a time t (25)@, and the ultrasonic propagation velocity in the body fluid v2 is calculated using the following formula.

V=(t-nτo)/(2n L(1) The stone is set by the τ0 setting device (7) in FIG.

From the sing-around circuit (8), information on the ultrasonic propagation velocity V passes through the gate circuit (113) and enters the CPU (12).

The voltage change of the temperature sensor (5) in FIG. The temperature information enters the CPU (12).

In the present invention, the memory circuit (18) stores a function F (T, V) for determining the specific gravity of the body fluid from the temperature (2) in the body fluid and the ultrasonic propagation velocity M.
As an example, constants of multi-dimensional polynomials are stored. In general, a multidimensional polynomial is given by: F=ΣaiTjVJ i * j, ;o−n)jk. This multidimensional polynomial is determined for each solution. The coefficient alt- is obtained by substituting the temperature, ultrasonic propagation velocity, and specific gravity according to the gravimetric method for each condition into the nine-dimensional simultaneous equation % formula, which is an example of a multidimensional polynomial, and at is stored in the memory circuit (18). . Coefficient ait-C from memory circuit (18)
PU (12) reads temperature information and ultrasonic propagation velocity V
The information is substituted into a function F(T·V) for weighting, and arithmetic processing is performed. The specific gravity value determined by the calculation is processed by the gate circuit (
11), enters the amplifier circuit (1), and the display circuit (1).
5) will be displayed.

〔Effect of the invention〕

According to the present invention, the specific gravity of body fluids can be measured continuously and quickly, and can be measured more easily than the conventional one-child method and floating scale method. Specific gravity can also be measured. Furthermore, vibrations and temperature fluctuations during measurement,
Due to the influence of liquid movement, etc., next, a complete comparison will be made between the urine specific gravity measured value, which is an example of the present invention, and the specific gravity value determined by the gravimetric method. Attached table 1
Table 2 shows the results of calculating the coefficient ai from the data of the fcJg temperature and ultrasonic propagation velocity measured using the apparatus according to the present invention shown in , and the specific gravity value measured by the gravimetric method. Attached Table 8 lists all the values of fc kettle specific gravity measured using an uninvented device and the values measured by the gravimetric method, and shows that the specific gravity measurement method according to the present invention is consistent with the specific gravity determined by the conventional gravimetric method. It shows.

〔Example〕

One embodiment will be described below with reference to the drawings.

Figure 2 shows the sensor unit (2), where the sensor unit (27) is immersed in body fluid.An electrical signal is sent through the cable (16) and the ultrasonic transducer (4). ,C ultrasonic waves are transmitted, reflected by the reflecting plate (8), received by the ultrasonic transducer (16), and sent to the cable (16) f!: electric signal.Ultrasonic transducer ( 4) is kept at a constant distance from the reflecting plate (8) by a holder (I8), and the cable (16) is fixed by a cable holder (17). 18) is a bent type holder in which the part that fully supports the ultrasonic transducer (4) and the reflection plate (8) and the holding part (19) close to the cable (16) are at an angle. Figure (cl is the second
This is a cross-sectional view taken along line A-A in Figure (a), looking in the direction of the ultrasonic transducer t4).
8).

Attached Table 1 *Differences by specific gravity of liquid temperature 2θ℃ relative to water at 4°C Attachment 8 *Specific gravity is for a liquid temperature of 20"C relative to water at 4°0.

[Brief explanation of the drawing]

FIG. 1 is a plotter diagram showing all the embodiments of the device according to the present invention, and FIG. 2(a) and FIG. is the second
This is a cross-sectional view taken along line A-X in Figure ta), looking in the direction of the ultrasonic transducer, showing an embodiment of the temperature sensor. FIG. 8 is a diagram for explaining the whole sing-around method. In the figure, (11 is a body fluid, (2) is a sensor part, (8) is a reflection plate, (4) is an ultrasonic transducer, (8) is a sing-around part, (is a temperature measurement circuit, (11) is is the gate circuit,
In (12), the CPU (15) is a display circuit. Patent applicant: Sumitomo Bakelite Co., Ltd. Figure 1 Figure 2 (a) Figure 3 Procedural amendment (voluntary) November 7, 1980 To the Commissioner of the Japan Patent Office 1 Indication of case 1989 Patent Application No. 78581 2 , Name of the invention Specific gravity measuring method and device 3, Relationship with the case of the person making the amendment Patent applicant address 1-2-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo Column for detailed description of the invention. (1) Add "+" after "a5V2" on page 6, line 8 of the specification. that's all

Claims (1)

[Scope of Claims] (1) A method for measuring specific gravity, which comprises propagating ultrasonic waves into a body fluid and calculating the total specific gravity of the body fluid by calculating from the ultrasound propagation velocity and the temperature of the body fluid. (2) All ultrasonic waves are transmitted and received by an ultrasonic transducer supported in the body fluid and a reflector supported while maintaining a certain propagation distance, and the ultrasonic waves are estimated from the ultrasonic propagation time and propagation distance of the body fluid. Calculate the back wave propagation velocity and calculate the total temperature within the body fluid.
What is claimed is: 1. A specific gravity measuring device using ultrasonic sound, comprising a circuit for calculating the specific gravity of a body fluid from the ultrasonic propagation velocity and the temperature of the body fluid. (8) In a holder that incorporates an ultrasonic transducer supported in body fluid and a reflector supported at a constant propagation distance, the ultrasonic transducer and the reflector are connected to the supporting part. ,
3. The specific gravity measuring device according to claim 2, wherein the holding portion close to the cable is a bent holder having an angle bar.